


Power Struggle

by Verchan



Category: Toaru Kagaku no Railgun | A Certain Scientific Railgun, Toaru Majutsu no Index | A Certain Magical Index
Genre: Abuse, Anal Sex, Clothed Sex, Creampie, Dirty Talk, Dubious Consent, F/F, Face Slapping, Futanari, Mind Break, Oral Sex, Rape/Non-con Elements, Rough Sex, Vaginal Sex
Language: English
Status: Completed
Published: 2019-01-11
Updated: 2019-01-11
Packaged: 2019-10-08 03:18:24
Rating: Explicit
Warnings: Rape/Non-Con, Underage
Chapters: 1
Words: 2,811
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/17378585
Author URL: https://archiveofourown.org/users/Verchan/pseuds/Verchan
Summary: Mugino's tired of being the Number Four under Misaka, and she finally found a way to come out on top.





	Power Struggle

“Fuck, you’re even tighter than Frenda and Kinuhata! ~”

“N-Ngh, s-stop…!”

Shizuri Mugino, currently the Number 4 Esper in all of Academy City, licked her lips eagerly and hungrily as she pinned Mikoto Misaka, the Number 3, against the wall, using her left hand to hold her in place. The Meltdowner’s thick, aching cock was buried deeply inside the Railgun’s tight ass, packed in snug and firmly, and there was nothing that the younger girl could do to resist. Not with the collar around her neck inhibiting her from using her electric powers.

The moment Misaka even tried to turn her head, Mugino used her right hand to grip Misaka’s short hair tightly and push her head back forward at the cold, metal wall. The two of them were situated in a large room with lots of empty space, the walls a blank white that blended in with the debilitating lights in the ceiling, with a one-way window at the top.

All in all, it looked just like one such room that the scientists of the Dark Side of Academy City used for the Level 6 Shift Project, not that Mugino or Misaka would exactly know that.

“I could get addicted to this!” Mugino grinned with a malicious, sadistic edge to her voice, pulling her thick meat out, only to just as abruptly and mercilessly shove it back into Misaka’s ass, causing the young teen to gasp sharply and whine.

“S-Stop…! Please… I-I’m sorry…!” Misaka whined as she was barely able to hold back pained tears.

“Oh, you don’t know the _meaning_ of sorry yet, you little bitch! But that’s okay, we’re not in any rush. By all means, take your _time_!” Mugino responded to Misaka’s pleas, drinking in every drop of the younger girl’s regrets that she had practically (perhaps even literally) drilled in her as she thrust inside once again, her fat nuts lightly slapping Misaka’s butt cheeks in the process.

…

Mugino had had her vendetta against Misaka ever since practically the first time they’d met, with her and the rest of ITEM facing off against the lone Electromaster.

The tea-colored beauty who went by the moniker “Meltdowner” deeply hated the idea of being considered lower than such a little brat who was barely even older than pre-teen, and to see it in action as Misaka managed to, by all technical means, get the better of them, was humiliating, but not as much as humiliating as the prospect that it “shouldn’t” have been humiliating, just like how it “shouldn’t” be a surprise that Accelerator would be able to beat Teitoku Kakine if they ever fought.

In other words, just as it was natural for the Number 1 to destroy the Number 2, it was natural for the Number 3 to overcome the Number 4.

And if she could help it, Mugino was _not_ going to let herself stay in fourth place forever. And that’s where the shady scientists of Academy City’s Dark Side, headed by the Kihara, came into play.

They had experiments they wanted to run, and Mugino volunteered. It was as simple as that on paper.

Anything to become stronger. Anything to get closer to the top.

Mugino admittedly glossed over the finer details of the experiment in question; things like those didn’t interest her so much if she didn’t have to know. Thus, she was in for quite the surprise when the experiments on her body were done, and before she knew it, she had grown a massive cock, heavy and sizable enough that she could barely stuff it underneath shorts, let alone the panties she was actually wearing before.

Really, she didn’t know what the better gift was for getting back at Mikoto Misaka. Her new cock, which intensified her emotions and even her physical strength (something about testosterone injections mixed with a mystery chemical, Mugino didn’t know the details as mentioned before), or the collar the scientists gave her, an experimental device that could theoretically deactivate an Esper’s powers for as long as they wore it.

She just had to use both gifts on Misaka. The Railgun never knew what hit her. Of course, Mugino had to bide her time. Like an animal acting on pure instinct, not used to the deep, passionate lust she felt, Mugino helped herself to Kinuhata and Frenda before anything, letting herself release her thick orgasm for the first time. With their young, ripe bodies right in front of her, how could she resist? They resisted at first, but came around easily enough, and surely, Misaka would be the same.

Call it a warm-up round to test out her new appendage.

And now, before Mugino knew it, here she was, finally enjoying the fruits of her labors once she had recovered enough to be able to carry out her revenge.

…

Misaka could feel every pain-staking inch of Mugino’s unbearably thick shlong. Her eyes were shut tightly as if to shut out the relentless pain, but it did nothing to assuage it, nor did the intense gritting of her teeth. Mugino’s length was just too powerful.

_SMACK! SMACK! SMACK!_

Each thrust echoed throughout, filling up the room as heavily as the musky smell of sex and the heat in the air. In between the forceful smacking sounds, soft schlicking noises could also be heard as Mugino’s thick rod rapidly moved in and out of Misaka’s ass, wet enough from Mugino’s pre-cum to allow for smoother dicking.

“G-Ghhngh, fuck, your ass feels soooo good, Misaka! ~” Mugino teased sadistically as she held her evil grin, slapping the girl’s ass hungrily.

“Tell you what though,” she continued, still maintaining her consistent pace of her hips bucking in and out, “If you admit to me that I’m stronger, that I’m better than you in every way, that I deserve the spot of Number 3 over you, then I promise I won’t cum inside!”

“W-What?! What are you… n-ngh, t-talking about?!” Misaka exclaimed incredulously through gritted teeth, her cheeks flushed a deep pink as she continued trying to withstand the sensation of Mugino’s powerful cock. “That’s… ridiculous! I don’t--!”

Misaka was cut off as Mugino, with her right hand still gripping Misaka’s hair as it always was, pushed her face against the wall once again, panting more rapidly now. “Go on, say it! Say it, you little bitch! I’m so close!”

“A-Aah!” Misaka yelped, letting out a pathetic whimper, “Y-You’re stronger than me, it’s true! You’re way better than me in every way! You deserve to have the title of Number Three! Please stop! Please—” The Ace of Tokiwadai, in her most shameful moment to date, exclaimed with that, but even so, it happened anyway.

“Y-Yes, yessssssss!!” Mugino practically shrieked as she buried her dick in Misaka’s ass all the way to her hilt, orgasming with the force of a river, shooting her cum inside as her balls twitched ever so slightly.

“Noooo!” Misaka screamed as the Meltdowner eventually finished cumming, pulling her thick cock out with a _plop_ sound, letting some excess cum spill to the floor. Mugino’s still-stiff dick bounced about slightly, even staining the woman’s own loose-fitting lavender dress to a small degree.

Even as she finished, Mugino still held her hand against Misaka’s head, keeping her fixed where she was. Licking her lips, the Number Four, or rather, the _former_ Number Four as Mugino felt inclined to see herself now, she let out a soft chuckle. “Mmm… That was amazing. Best nut I’ve ever had so far.”

“Y-You said… You said you wouldn’t…!” Misaka tiredly said, barely having enough energy to even finish her own sentence.

“I did, didn’t I? But you should have caught on by now…” Mugino said, maintaining her triumphant grin as, with strength that even Misaka was surprised by (as the Electromaster expected Mugino to be all spent now), completely turned the middle schooler around, letting them face each other finally, with Misaka’s back against the wall now instead of her front.

“… I lied.”

“You… I can’t believe you—” Misaka began but was once again cut off as Mugino leaned in and harshly pressed her lips against Misaka’s, giving her a toxic, almost hateful kiss, as though to silence the young girl right there, molesting her flat chest with her hand while she was at it, toying with and pinching her nipples through her school uniform.

Misaka didn’t dare to even bite Mugino’s tongue, as much as she would have liked to, as she didn’t want to know what sort of awful punishment would be in store for her if she did, so she kept on relenting, but she didn’t know just how much longer she could take at this rate!

After a prolonged moment, Mugino finally pulled away, letting out a hot breath as a saliva trail formed between their lips. Misaka had never been fucked before, let alone even had a kiss. And with both her anal virginity and her first kiss stolen, it was more than enough to silence Misaka, if only as she stood there, stupefied. It was prime time to take advantage of the opportunity.

With her cock, still standing erect the entire time, poised and ready to cum again, Mugino took a hold of Misaka’s arms with both hands and pinned them against the wall forcefully, her expression still not changing for a second as she reveled completely in her victory and her lust.

“Hmm, I wonder if I can impregnate anyone with this cock. Care to find out?”

“W-What?! No, s-stop! Please!” The younger Level 5 frantically shook her head, still attempting to break free of the woman’s grasp but still to no avail.

“Shh, don’t worry. It might hurt a bit at first, but I assure you, it’ll feel so good when you let go and stop being scared,” Mugino said with a sinister edge, barely able to hide it underneath her faux soothing words. With Misaka’s ass still sore from the pounding it just took, the girl couldn’t bear to know how her pussy would take it.

But she found out sooner than she would have liked.

A deep scream escaped Misaka’s lips as Mugino’s aching cock was thrust into her pussy, slamming in hard, and fucking her without mercy, pulling in and out faster than Misaka could even begin to process each individual thrust. Mugino packed enough power in each thrust that Misaka was practically bouncing up a little, the loud smacking noises returning as their thighs slammed against each other.

“Nnngh ~” Mugino moaned with delight as she mercilessly kept thrusting, every _smack, smack, smack_ gradually growing louder with every powered thrust. Her eyes rolled back as she could hardly contain the pleasure she got from penetrating Misaka’s inner walls, basking in her warmth, making the girl truly hers.

And before Mugino knew it, it began to happen. Misaka started to become hers.

Mugino could feel Misaka’s body go limp, and gradually, slowly but surely, the girl’s resistant moans began to quiet down until her sounds became that of a broken slut’s. Anguished screams became ecstatic mewls as the look in Misaka’s eyes became hazed, empty. She was destroying the girl’s mind, right on cue.

_SMACK!_

“Ahhn! ~”

From there, Mugino had suddenly raised an arm and slapped Misaka across the face, letting the sound ring through the empty room. The girl let out a sharp gasp, but not a pained one. If anything, one could be led to believe she _liked_ it. And Mugino never thought the girl looked any hotter than she did right here.

“Yeah, you like it now, don’t you?” Mugino said madly, overcome by her uncontrollable lust as she gave another sharp slap, all the while continuing to pump her cock in and out, burying it all the way to her hilt until her balls touched her thighs, “Tell me who you belong to! Tell me who your pussy belongs to!”

“YOU!” Misaka bellowed, louder than she’d ever been in the room, and without a hint of shame or apprehension on her voice, “I-I belong to you, Miss Mugino! Don’t stop! Oh god, don’t stop!”

Without a shadow of a doubt now, Mikoto Misaka had been definitely broken in by Mugino’s magnificently thick cock, a slave to her own desires, or perhaps more literally, a slave to Mugino’s desires.

“Ngh, you’re so cute! ~ Seeing you like this, dear Railgun… I’m getting close again! More, more! Say it again!” Mugino said, panting like a dog in heat as her thrusts became more and more aggressive, on her way to completely ruining Misaka’s wet, sweet pussy.

“M-Mistress…! Your cock feels so good! Please give it to me! I-I don’t ever want to be without it! Ahhn! I-I’m gonna cum too!” Misaka moaned, dripping uncontrollably onto the floor as she looked submissively in Mugino’s eyes.

_SMACK!_

Mugino gave Misaka another firm slap just for the thrill of it, but the girl didn’t mind. She welcomed the sensation of being touched by her mistress.

“Let’s cum together then, Number Four! By the time I’m done with you, you’re gonna be good for nothing but being a breeding pet!” Mugino exclaimed excitedly. Before Misaka could respond in any way, the taller woman leaned in and stole another kiss from Misaka, even going as far as to suck on her tongue and practically drink up her saliva.

And with that, Mugino’s entire body went as stiff as her cock as she came buckets inside Misaka’s waiting pussy, painting her insides white. As Mugino unloaded her heavy load inside, Misaka’s eyes rolled back once more, muffled screams of pleasure barely able to be heard as her mouth was still covered by Mugino’s.

The new self-appointed Number Three had came so much that Misaka’s small belly had almost seemed to get bigger by just a little, as though she was filled up with that much cum. Eventually, Mugino pulled away from the kiss, and with a satisfied groan, pulled her cock out of Misaka’s pussy as well with another _plop_ sound like the last time she came and pulled out. Mugino had finally let go of Misaka’s arms and stepped away, letting the girl unceremoniously slide down and land on the ground on her tight bottom like a broken, used-up toy.

With a hazed, broken gaze, Misaka could only breathe heavily, slowly moving her head down to look at the surplus of cum leaking from her pussy. Before long, her attention was directed back to Mugino, who stepped forward, letting her cock, which was slowly becoming limp and flaccid as she calmed down, stand in front of Misaka’s face. With her hands poised on both her hips now, Mugino gestured briefly to her cock.

“Clean me up, pet. From now on, you’re gonna get used to this treatment,” she demanded with a knowing smirk, to which Misaka eagerly obeyed.

“Y-Yes, mistress…” She nodded obediently, raising her hands to cup and fondle Mugino’s fat nuts while she moved her face in to worship Mugino’s cock. The thick smell of her natural musk intoxicated Misaka like a drug. The heat, the sweat, it was all enough to make anyone go crazy for Mugino. Her tongue slid up and down across Mugino’s meat rod, lapping up any cum that was dripping down, some of which had managed to drip as low as to her balls.

As Misaka got to work, Mugino let out a soft breath, standing still exactly where she was as she began musing to herself.

“Mmm, can’t believe all it took was a collar and a cock to tame the Railgun,” Mugino chuckled, “With all this, I could breed any girl I wanted. Maybe I’ll break in Mental Out next. Gotta make sure Shokuhou doesn’t try to take my new Number 3 spot now. Isn’t that right, Number Four?”

Misaka didn’t respond, too busy worshiping Mugino’s cock. She had quickly gone from licking and teasing it to kissing it, and then even taking the whole thing in her mouth, blowing Mugino as she bobbed her head back and forth.

“Aha, well, I guess if you won’t respond, it may as well be because your mouth is busy otherwise,” Mugino laughed briefly, petting Misaka’s head briefly, “Hmm… I could also do in your little friends while I’m at it. At least that way you won’t be lonely,” she cackled softly.

By the time she finished talking, Misaka only continued sucking Mugino off, part of her head even partially obscured by Mugino’s lavender dress as she grew more and more eager. Mugino didn’t quite need a response anyway. After all, what was Misaka’s input worth now that she was the way she was?

With the girl’s pert lips wrapped around her aching member, Mugino could only revel in her victory, leaning her head back and licking her lips.

Who needed the Level 6 Shift Project when she could move up the ranks this way?


End file.
